--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/clear_map.h	Wed Jan 03 08:49:36 2007 +0000
@@ -0,0 +1,145 @@
+/* $Id$ */
+
+#ifndef CLEAR_MAP_H
+#define CLEAR_MAP_H
+
+#include "macros.h"
+#include "tile.h"
+
+/* ground type, m5 bits 2...4
+ * valid densities (bits 0...1) in comments after the enum
+ */
+typedef enum ClearGround {
+	CLEAR_GRASS  = 0, // 0-3
+	CLEAR_ROUGH  = 1, // 3
+	CLEAR_ROCKS  = 2, // 3
+	CLEAR_FIELDS = 3, // 3
+	CLEAR_SNOW   = 4, // 0-3
+	CLEAR_DESERT = 5  // 1,3
+} ClearGround;
+
+
+static inline ClearGround GetClearGround(TileIndex t)
+{
+	assert(IsTileType(t, MP_CLEAR));
+	return GB(_m[t].m5, 2, 3);
+}
+
+static inline bool IsClearGround(TileIndex t, ClearGround ct)
+{
+	return GetClearGround(t) == ct;
+}
+
+
+static inline uint GetClearDensity(TileIndex t)
+{
+	assert(IsTileType(t, MP_CLEAR));
+	return GB(_m[t].m5, 0, 2);
+}
+
+static inline void AddClearDensity(TileIndex t, int d)
+{
+	assert(IsTileType(t, MP_CLEAR)); // XXX incomplete
+	_m[t].m5 += d;
+}
+
+
+static inline uint GetClearCounter(TileIndex t)
+{
+	assert(IsTileType(t, MP_CLEAR));
+	return GB(_m[t].m5, 5, 3);
+}
+
+static inline void AddClearCounter(TileIndex t, int c)
+{
+	assert(IsTileType(t, MP_CLEAR)); // XXX incomplete
+	_m[t].m5 += c << 5;
+}
+
+static inline void SetClearCounter(TileIndex t, uint c)
+{
+	assert(IsTileType(t, MP_CLEAR)); // XXX incomplete
+	SB(_m[t].m5, 5, 3, c);
+}
+
+
+/* Sets type and density in one go, also sets the counter to 0 */
+static inline void SetClearGroundDensity(TileIndex t, ClearGround type, uint density)
+{
+	assert(IsTileType(t, MP_CLEAR)); // XXX incomplete
+	_m[t].m5 = 0 << 5 | type << 2 | density;
+}
+
+
+static inline uint GetFieldType(TileIndex t)
+{
+	assert(GetClearGround(t) == CLEAR_FIELDS);
+	return GB(_m[t].m3, 0, 4);
+}
+
+static inline void SetFieldType(TileIndex t, uint f)
+{
+	assert(GetClearGround(t) == CLEAR_FIELDS); // XXX incomplete
+	SB(_m[t].m3, 0, 4, f);
+}
+
+static inline uint16 GetIndustryIndexOfField(TileIndex t)
+{
+	assert(GetClearGround(t) == CLEAR_FIELDS);
+	return _m[t].m2;
+}
+
+static inline void SetIndustryIndexOfField(TileIndex t, uint16 i)
+{
+	assert(GetClearGround(t) == CLEAR_FIELDS);
+	_m[t].m2 = i;
+}
+
+/* Is used by tree tiles, too */
+static inline uint GetFenceSE(TileIndex t)
+{
+	assert(IsTileType(t, MP_CLEAR) || IsTileType(t, MP_TREES));
+	return GB(_m[t].m4, 2, 3);
+}
+
+static inline void SetFenceSE(TileIndex t, uint h)
+{
+	assert(IsTileType(t, MP_CLEAR) || IsTileType(t, MP_TREES)); // XXX incomplete
+	SB(_m[t].m4, 2, 3, h);
+}
+
+static inline uint GetFenceSW(TileIndex t)
+{
+	assert(IsTileType(t, MP_CLEAR) || IsTileType(t, MP_TREES));
+	return GB(_m[t].m4, 5, 3);
+}
+
+static inline void SetFenceSW(TileIndex t, uint h)
+{
+	assert(IsTileType(t, MP_CLEAR) || IsTileType(t, MP_TREES)); // XXX incomplete
+	SB(_m[t].m4, 5, 3, h);
+}
+
+
+static inline void MakeClear(TileIndex t, ClearGround g, uint density)
+{
+	SetTileType(t, MP_CLEAR);
+	SetTileOwner(t, OWNER_NONE);
+	_m[t].m2 = 0;
+	_m[t].m3 = 0;
+	_m[t].m4 = 0 << 5 | 0 << 2;
+	SetClearGroundDensity(t, g, density);
+}
+
+
+static inline void MakeField(TileIndex t, uint field_type, uint16 industry)
+{
+	SetTileType(t, MP_CLEAR);
+	SetTileOwner(t, OWNER_NONE);
+	_m[t].m2 = industry;
+	_m[t].m3 = field_type;
+	_m[t].m4 = 0 << 5 | 0 << 2;
+	SetClearGroundDensity(t, CLEAR_FIELDS, 3);
+}
+
+#endif /* CLEAR_MAP_H */